CLASS I 



PELECYPODA 



495 



Fir.. 815. 



TelUna planata Lum. Miocene; Putzleinsdorf, 

 near Vienna. 



Fig. 810. 



Tcllina rostralina Desh. Eocene ; Damery, 

 near Epernay. 



Fig. 817. 



Tcllina (Linearia) hiradiata Zittel. Upi)(;r 

 Cretaceous ; Gosau, Austria. 



Family 34. Semelidae Dal]. 



Resembling the Tellinidae, but with the resilium internal, often on a distinct chondro- 

 ■phore, and with the laterals, when present, stronger and less distant. Tertiary to Eecent. 



Semele Sclium. (Amphidesma Lam.). Shells large, rounded, thick, often conspicu- 

 ously sculptured; 100 species. Tertiary and 

 Recent. 



Gumingia Sow. Small, thin, with a spoon- ^ 

 like chondrojihore ; habit nestling. Tertiary 

 and Eecent. 



Scrobicularia Schum. Differs from Semele in 

 having no lateral teeth. Tertiary and Recent. 



Abra Leach {Syndosmya Recluz) (Fig. 818). 

 Smooth, small, thin ; cardinals 2:2, an anterior and posterior lateral present ; 

 chondrophore narrow, oltlique, not separated from the hinge line. Tertiary and 

 Recent ; chiefly in deep water. 



Family 35. Psammobiidae DaU. 



Shell as in the Tellinidae, but usually more 

 equivalve and less twisted, with more conspicuous 

 epidermis and nymphs, broader hinge-plate, and 

 a ivider posterior gape; lateral laminae on the 



Fig. 818. 



Abra ajielina {Jim\.). Miocene; Grund, 

 near Vienna. 



Fig. 819. 



Psammohia effiisa Desh. Eocene (Calcaire 

 Grossier) ; Parnes. 



Fi<;. 820. 



Psammosolen (Mcwha) deshayesii (Desm.). Calcaire 

 Grossier ; Grignon, near Paris, i/j. 



